function resetSearchField(field, prefill) {
    field.value = prefill;
  }

  function changeSearchField(field, prefill) {
    if (field.value == prefill)
      field.value = '';
		else if (field.value == '')
      field.value = prefill;
  }

  function fieldSearchEmpty(field, prefill) {
    return (field.value == prefill || field.value == '');
  }

  function checkSearchForm(form, prefill, msg) {
    var field = form.q;
    if (fieldSearchEmpty(field, prefill)) {
      resetSearchField(field, prefill);
      return false;
    }
    return true;
  }